Cochlear prostheses and other implantable biomedical devices are requiring increasing rates of data flow inward for control purposes and outward for monitoring. Percutaneous connectors are inadequate for many future applications because of their limited contact densities, cosmetic consequences, and paths for infection. The alternative of combined radio-frequency coil links for data and power have inherent bandwidth limitations. Having established the feasibility of high-speech optical data links through the skin, we proposed to design fabricate and test the first two-way, high-speed transcutaneous optical links. The internal subsystems will be powered by ratio-frequency energy transferred through coils. The data links will use recently developed, very low power, light-emitting devices having different wavelengths for the inward and outward links. Errors due to link crosstalk, ambient light, tissue properties, movement, and other factors will be measured and the external and internal subsystems optimized to minimize them. Data rates in excess of 10 Mbits/s for the inward link and 1 Mbit/s for the outward link appear feasible. This technology has potential use in a number of biomedical areas, especially for neural and neuromuscular prostheses. PROPOSED COMMERCIAL APPLICATION: NOT AVAILABLE